Randhawa, of Grove Lane, Tettenhall, who had previously pleaded guilty to attempting to import explosives, was remanded in custody and is due to be sentenced on 12 January.

He was convicted of maliciously possessing an explosive substance with intent to endanger life or cause serious injury.

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Two women, aged 45 and 18, were also arrested at the same time but were released without charge.

Tim Gregory, from the NCA's armed operations unit, said: "The explosive device Randhawa sought to purchase online had the potential to cause serious damage and kill many people if he had been successful in using it.

"He was not involved in an organised crime group or linked to terrorism, but is clearly an individual who poses a significant risk to the community."